Application of E-radiation formula due to acceleration of a point charge:

For 1D-plane wave case – simple case: (Assume q > 0)

(Source is a current sheet)

For point charge case, notice only a-perp contributes.As is convenient, do the vector decompositions as indicated.At P the direction of E-rad detected is indicated by the dashed vector.

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Lecture 37

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EM waves in a vacuum are specified by one thing:

EM wave spectrum:

EM Waves

Radio Station KLBJ

Example of EM waves:Radio AM stadium 103 m

Microwaves Bean size 102 m

Visible Light Micrometer 600 nm

X-Ray Atomi size 10-10 m

increasingfrequency

increasingwavelength

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Sinusoidal in x:

λ is a conversion factor from x-scale to angle-scale

Period:

Fix phase: Defines the speed the fixed shape travels

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Radiation Field Due to Sinusoidal Oscillation of a Point Charge

Along x (or more generally, along r):Φ is the initial phase angle of the oscillation

Fix :

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